70s schwinn speedster project.

That chain looks crazy loose
Yeah, that's cuz the whole engine twisted to the right.
YEP, Thats because of his front motor mounting system he used Gordy...lol...To much flex in it due to torque of motor and jackshaft system being used with the mount being held by only two very long studs.

I'm just going to mount the engine normally, no silly spacers. I'll see about making my own clamp, I don't know if I'll have time in Machine Tool I to do any personal projects. Even if I don't have access to a laythe and a bridgeport, I said it in another thread but it could be done easily enough with hand tools and a power drill out of mild steel bar stock.

Will post pictures tomorrow, but I've decided to reorient the project. I'm going back to the single speed drive train for the engine but I want to make a drive by wire system and have it be pedal assist. But before that I want to try drop bars and a friction shifter as the throttle. My hope is that it'll make the ride less "hands on" when it comes to managing the engine so I can have a riding experience where the engine is helping the rider rather than the other way around.

I know I could get a more powerful engine, but I've grown fond of this kit and I don't want to give up on making it fun for me to ride.

While the PAS is completely possible, and would be very cool, if a simple friction shifter works well enough, then I'll save my time and money. Plenty of people have done diy drive by wire in rc and motorsports projects, and it would be very easy to program, especially with my occupational training, but it would be relatively expensive. My estimation is at least $200 to build a sturdy enclosure and purchase the electronics.

I've got a coaster brake to upgrade, and some components to "modernize" the bike that need to be installed. I've got a seat post that will let me use a saddle I really like, and an ashtabula to BSA bottom bracket adapter.
All of this is real inside baseball but I suppose I didn't live up to my promise of "Tomorrow."

Changed the seat for one I like better. Had to change the post too but it was cheap.

Installed an ashtabula to bsa adapter, lets me use the torque sensing bottom bracket should I decide to pursue drive by wire. Also lets me use modern bearing bottom brackets with sealed bearings. With the original one piece cranks I couldn't clear the engine, but with the 3 piece I can. I know the wide one piece cranks exist but I would have had to change the cup races in the frame because schwinn cranksets have different bearing assemblies to the other kind of one piece cranks, and also use a different thread pitch.

Got the drop bars on it: using a problem solvers travel agent to get the clutch and the short pull levers to play nice, and I'm using a bar end friction shifter as the throttle. Clutch works right, throttle gets pulled by the shifter and springs back like it should when released. So far everything works well.

Waiting on a chromoly axle to come in for making an actually safe coaster brake. With the weight of the bike and the single speed drive train for me and the engine I think a little above 20 mph is the fastest It will actually run. I know it could hypothetically go faster but with all the hills, and again the weight of the build that's not likely. I am not inclined to push these things faster than I can pedal a regular bike anyhow.

Really liking how the bike looks now though. Wrote it here before but my repetitive stress injuries make fully upright positions and wide bars very uncomfortable. The cold has been real rough on my joints.


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Got the engine bolted on. Thanks to the 3 piece cranks I have no clearance issues. I think the cables are as clean as can be. Turns out the pull is way too hard with the travel agent and the levers can engage the clutch without the adapter. Axle came in so I'll supe up that coaster brake after work.


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Chains wont align. Either the engine or the human side is loose. Either of my tensioners cant take up enough slack.


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Here's some pictures of it with the pedal side tight and the engine side loose.

I am thinking about buying an arch tensioner but I am halfway done fabbing my own.

I had a big write up on mounting the engine and rack, but it got lost. The pink struts are dimpled which give a stiffer construction than my attempt at struts.


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Have you ever thought of just taking out enough links where you do not even need a tensioner like I have done with mine???

Either of my tensioners cant take up enough slack.
So that also means that even with tensioners, there are still too many links in the chain for it to work anywhere near as good as what it needs to.